The octopus has advanced intelligence despite 500 million years of separate evolution from mammals, birds, insects and reptiles. Octopus ancestors are, perhaps, the first intelligent beings on Earth. Recent research is beginning to describe their very unusual talents, behavior and brain, as well as their unique genetic makeup. The fact that such an intelligent creature has no bones or spine has upended theories of animal intelligence. There are many different factors that come into play making this sea creature one of a kind.
Octopus Unique Intelligent Behavior
Octopuses are masters of getting through mazes and can solve advanced problems. They spread cultural information, mimic others and communicate using colors, patterns and flashing. They pick up coconut shell halves, carry them along and if threatened, flip them over their head to conceal themselves. Before their discovery of coconuts, they used shells. With two shells, they see through a small opening slit between the two halves. They can change their appearance with camouflage, so they can hide in plain sight near a wide variety of plants and corral, as well as mimicking other creatures. This is important for protection since they don’t have teeth or claws. They have advanced spatial learning, navigational abilities and use creative predatory techniques. Octopuses manipulate objects as well as the human hand and can escape from almost anything. They learn and can solve complex problems like crows.
Octopuses adapt to being captured in several days, unlike many other animals. The change is from a fearful animal to almost pet like—friendly and very alert about all that is occurring nearby. Octopuses respond rapidly to rewards and are extremely curious and responsive. They focus on any new object they see. When experimental probes are done in the nervous system, they rapidly recover and regenerate missing tissue. Octopuses are extremely and rapidly adaptive. They learn by watching others, do tricks with visual discrimination and they remember exactly for weeks. Their brain uses the same circuits for social learning and for other memory.
The octopus has very unusual abilities that make it unique among intelligent animals, such as camouflage and control and regeneration of eight flexible arms, each with thousands of suckers. Two of their relatives—squid and cuttlefish—are, also, unusually intelligent. Their eyes are like a camera with a lens, iris and retina. They have large unique brains and closed blood circulation with three heart.
Octopuses have photosensitive cells (opsins) in their skin that can determine colors of their close surroundings (similar to rhodopsin in the retina). In evolution it appears that one mollusc developed this protein in the skin and then later the octopus and other cephalopods adapted this to help with camouflage. These colors are used to determine camouflage, not the eye, which sees very accurately but not in color. Camouflage is an important strategy for defense since they have no teeth, claws or shell. They developed camouflage to such an extent that they can survive in any situation.
Suckers are quite independent.They move, sense (taste) and grasp independently, forming a very tight seal under water even on rough surfaces. Although soft as a jellyfish the attachment is incredibly strong using a cavity at the top with flexible sides making pressure. They have many grooves that are used to make a seal on rough irregular surfaces. The top is stiff (acetabular protuberance) while the sides and edges (infundibulum) are soft. Both stiff and elastic parts make a unique suction that becomes stiffer once contact is secure and with more pressure.
The Octopus Brain
The octopus brain is similar in relative weight with vertebrates—larger than reptiles and fish, smaller than mammals and birds. It has 500 million neurons, which is similar to a dog, six times more than a mouse. The octopus brain is split into two halves and then into many lobes with particular functions. These lobes are folded, which increases the surface areas and connections. Some regions have very small neurons where large numbers can be packed into a small compartment. Also, the distance between them is very short, which increases processing speeds.